Damian McBride's account of Miliband's political ruthlessness in his new book doesn't suit the Tories' narrative.

Ed Miliband delivers his speech on reforming the Labour-trade union link at The St Bride Foundation in London on 9 July 2013. Photograph: Getty Images.

The Tories have long counted down the days until the serialisation of Damian McBride's memoir in the Daily Mail in the hope that it will provide them with plentiful ammunition to hurl at Ed Milband in the run-up to Labour conference. But judging by the extracts published today, it could prove less helpful than they'd hoped.

If there is one word that David Cameron has sought to associate with Miliband in recent months it is "weak". But rather than a feeble, spineless character, the Miliband who emerges from the pages of Power Trip is a strong and ruthless figure. Here are three notable examples from today's extracts.

1. McBride confirms that Miliband "effectively threatened to resign from the cabinet" over the planned third runway at Heathrow, a move that successfully torpedoed the policy. He adds that Ed Balls was angry that Brown "had been made to look weak" in front of his cabinet by "having to kowtow to a supposed ally". The story of how Miliband defied the PM and his political patron hardly suits the Tory narrative.

2. We are also reminded of how Miliband dared to stand against his brother, long considered Brown's heir apparent, for the Labour leadership. That might not seem significant but the Tories have recently stopped referring to how Miliband "knifed" his brother out of fear that it undermines their framing of him as "weak".

McBride also writes insightfully about how Miliband's loyalty to his father's socialist ideals may have prompted him to run against David:

It’s hard to listen to any of Ed Miliband’s occasionally tortured, over-academic speeches without hearing his father’s voice, especially when he talks about recasting the capitalist model and re-shaping society through the empowerment of ordinary people.

And that’s not just about Ed’s politics; it’s also undoubtedly central to how he explains to himself and to the rest of his family why he challenged his older brother for the Labour leadership.

What better reason than needing to achieve his father’s vision and ensure David Miliband did not traduce it? An act of supposed disloyalty to his brother becomes transformed in his mind into the ultimate act of tribute to his father.

3. At PMQs in 2012, David Cameron mocked Miliband over claims in the Daily Mail that he used to fetch coffees for Ed Balls when the pair were both Treasury advisers to Gordon Brown. He said: "Apparently, he still has to bring him the coffee. That's just how assertive and butch the leader of the opposition really is."

This fits with the Tory narrative of Miliband as a put-upon junior to Balls, Brown's star pupil (a relationship, they suggest, that is unchanged). But McBride scotches this account:

At the Treasury, the two Eds were a double act. The idea Miliband was ever made to feel subordinate to Balls is baloney, along with the myth of him bringing Balls his morning coffee.